Over the past several years, the popularity of golf has soared, leading to a great number of inventions that allow a player to get enjoyment by playing a simulated game or to practice by using a machine to analyze a player's golf swing.
Particularly relevant to game simulation are inventions in the prior art using gesture recognition to allow a player to make realistic movements that are mimicked on a video display. For example, a player playing a simulated golf game can use a real or mock golf club to make the movements of an actual golf swing and see the mimicked swing on a video display followed by the graphical representation of a golf ball flying off a graphical tee, hopefully towards a graphical hole. U.S. Pat. No. 5,453,758, issued to Sato, for “Input Apparatus” “outputs as operator information the position specifying information obtained by detecting input apparatus's physical displacement, movement velocity, or acceleration to generate a predetermined command signal corresponding to movements of a human being for example”. Sato further discloses using an oscillation gyroscope to sense angular velocity and a temperature sensor to correct errors in movement related data caused by changing temperature conditions. U.S. Pat. No. 5,516,105, issued to Eisenbrey, et al., for “Acceleration Activated Joystick” discloses a “video game user interface device that allows the user to play standard video games using realistic arm, leg and body movements which relate to the various activities portrayed in the video game being played. The device is sensitive to acceleration and outputs a signal to the video game controller when an acceleration is detected.” U.S. Pat. No. 5,704,836, issued to Norton, et al., for “Motion-Based Command Generation Technology” discloses a command system that “optically monitors the movement of a subject and provides command signals to a computer system to control a graphic of a graphical user interface displayed on a monitor such as an animated character in a video game.” Norton accomplishes this by using an “optical detector unit which continuously scans a subject frame in which a subject is positioned” and comparisons of scans of sub-regions in the frame to determine if the subject has moved. Once movement is detected, the graphical representation on a video screen can simulate the movement. U.S. Pat. No. 5,718,639, issued to Bouton, for “Opto-Electric Golf Club Swing Sensing System Having Vertically Offset Sensors” discloses a “video golf swing sensing system responsive to a user swinging a golf club” that “provides inputs to a video golf game operating on a personal computer having a monitor, a microprocessor, and a serial port.” Bouton uses a sensing system comprising linear arrays of LEDs and photodetectors “for detecting a club head parameter by sensing light reflected off the club head.” These gesture recognition apparatuses and methods in the prior art use sophisticated mapping schemes to let a user participate in simulated activities using motions that would be used in the real activity.
Particularly relevant to golf swing analysis are inventions in the prior art that measure certain characteristics of a golf swing such as club speed and position. U.S. Pat. No. 5,108,105, issued to Shimizu, for “Golf Practice Device” discloses a “golf practice device comprising a mat with at least two sensors arranged therein in the direction of a swing orbit of a head of a golf club. A swing time substantially from a start of a back swing to a point of an impact with a golf ball is calculated in response to signals output by the sensors, and the result is indicated so that a golfer can observe same and thus achieve a stable swing.” U.S. Pat. No. 5,257,084, issued to Marsh, for “Golf Swing Measurement System” discloses “A technique for measuring golf swing tempo or clubhead speed for a golfer swinging a golf club through a tee area. Two parallel infrared (IR) transmitters transmit respective IR beams along predetermined lines toward the tee area. Respective IR sensors receive respective IR beams reflected from a reflector mounted to the shaft of the golf club, near the clubhead. Each IR sensor provides a respective output signal indicative of the passage of the golf club through a corresponding IR beam. Predetermined sequences of output signals from the IR sensors are detected and the differences in time between various output signals are measured to provide tempo and clubhead speed values for display on a LCD screen. The speed values can be compensated values as obtained from look-up tables.” U.S. Pat. No. 5,692,965, issued to Nighan, et al., for “Golf Swing Training Device With Laser” discloses an apparatus that uses at least one laser device that provides a feedback signal to the golfer that is indicative of a position and a motion of the head during the top of a backswing of the golf club by the golfer.” The laser device may also be used to project a beam that provides visual feedback to the user, such as by showing a path on the ground or the motion and position of the golf club head. U.S. Pat. No. 6,375,579, issued to Hart, for “Golf Swing Analysis System And Method” discloses a laser based system that uses a monochromatic laser projector to generate a series of light planes in space near the impact zone where the golf club impacts the golf ball and a laser-based attachment for the golf club. This system and method attempts to analyze an entire golf swing by measuring certain characteristics of a golf swing as it passes through the impact zone. U.S. Pat. No. 7,219,033, issued to Kolen, for “Single/Multiple Axes Six Degrees of Freedom (6DOF) Internal Motion Capture System with Initial Orientation Determination Capability” discloses “A highly miniaturized electronic data acquisition system includes MEMS sensors that can be embedded onto moving device without affecting the static/dynamic motion characteristics of the device. The basic inertial magnetic motion capture (IMMCAP) module consists of a 3D printed circuit board having MEMS sensors configured to provide a tri-axial accelerometer; a tri-axial gyroscope, and a tri-axial magnetometer all in communication with analog to digital converters to convert the analog motion data to digital data for determining classic inertial measurement and change in spatial orientation (rho, theta, phi) and linear translation (x, y, z) relative to a fixed external coordinate system as well as the initial spatial orientation relative to the known relationship of the earth magnetic and gravitational fields. The data stream from the IMMCAP modules will allow the reconstruction of the time series of the 6 degrees of freedom for each rigid axis associated with each independent IMMCAP module.” Kolen further teaches putting an error representation on a display. U.S. Pat. No. 7,785,211, issued to Hackenberg, for “Golf Swing Trainer Having Balanced Center Of Mass” discloses a “golf swing trainer providing a resiliently flexible shaft having a first shaft end coupled to a swing element and a second shaft end coupled to a grip having a tapered external surface gripably received by the hands.”
Inventions involving golf swing analysis have also involved attaching cameras to a golf club and using data produced by the camera to analyze the movement of the golf club. U.S. Pat. No. 7,536,033, issued to Kirby, for “Portable Swing Analyzer” discloses an apparatus with “an imaging system in communications with the sporting equipment to measure motion parameters. The imaging system may be located on the sporting equipment or, optionally, within the sporting equipment.” The system may be used to determine the impact location of the sporting equipment with another object, the momentum transferred, the velocity of the sporting equipment and/or the angular orientation of the sporting equipment during a motion. Such determinations are accomplished by “(a) a means of taking sequential images attached to said swinging type piece of sporting equipment, the sequential images being of a background element that does not move with the sporting equipment; (b) a means of identifying a common pattern between two sequential images and calculating a displacement vector from the movement of said common pattern in communication with said means of taking sequential images; said displacement vector representing the displacement of said common pattern between said sequential images; (c) a means of interpreting said displacement vector in communication with said means of calculating a displacement vector, the interpretation providing the user a meaningful set of information concerning the use of said sporting equipment; and (d) a means of communicating to user said meaningful set of information concerning the use of said sporting equipment, in communication with said means of interpretation; whereby the user may analyze their performance in the use of said sporting equipment.” Likewise, Japanese Patent number JP2010274089 discloses a golf training putter that “includes at least two or more cameras, one or more of which include the cameras at positions higher than a head in a shaft. An angle sensor is required at the same time.” “[A] gyro sensor, an acceleration sensor and distance sensor are combined together. From information of the cameras, the swing orbit, a distance to the ball and an inclination between the ball and the cup are clarified.”
Inventions involving golf swing analysis have also involved attaching lasers to a golf club and using the laser lines to analyze the golf swing movement of a golfer. U.S. Pat. No. 5,873,789, issued to Torriano, for “Golf Swing Training Device” discloses “A golf club shaped swing training device provides visual indication of club position during a club swinging motion. A first laser diode produces a first laser line from the upper end of the shaft and second and third laser diodes produce second and third laser lines respectively from the bottom face and the front face of the head portion of the device. Each of the laser lines emanates from the device as a concentrated beam to impinge and be readily visible on a training surface remote of the device for independently tracking movement of the shaft, the bottom face and the front face of the head portion of the device.” U.S. Pat. No. 8,409,024, issued to Marty, et al., for “Trajectory Detection and Feedback System for Golf” discloses “Lining up the direction of the shot may take place in advance of the shot by positioning a laser line on the view of the virtual course. Then the calculated shot may be positioned on the virtual course based on how the actual swing and golf ball were struck. The system may allow communication connections that allow each of the players to see the results of their shots on the real or virtual course.
The prior art is deficient because it does not provide a system, apparatus or method of providing an attachment to a golf club that detects and measures the movement of the golf club through an entire swing, that displays the entire swing movement of the golf club on a graphical display along with relevant statistics, that provides coaching using theoretical and historical data with graphical and verbal feedback, and that corrects errors with great precision. The prior art is also deficient because it does not provide for swing plane analysis of an entire swing by simulating laser lines that would be reflected on the ground as if laser lights were mounted and aligned on a golf club shaft, each emitting light from a respective end of the golf club shaft. The gesture recognition techniques described above are deficient because they are merely used as input for games and simulations and are not used to record and analyze all major aspects of a full golf swing and to provide feedback and coaching to a user so that user may improve his or her golf game. The golf swing analysis techniques described above are deficient because they attempt to analyze an entire swing using only a small portion of the swing. limit the number of statistics or graphics, such as club speed or error representation, do not use a real golf club, or do not provide adequate error correction for the inertial measurements. Additionally, many inventions in the prior art require a fair amount of equipment, making them costly.
The prior art is also deficient because it lacks adequate error correction for measurements taken during an entire golf club swing. Error correction may be accomplished using a camera directed at the club head with image recognition software and data from a navigation system. The data from the camera and the image recognition software may be used to measure the distance between a golf ball and club head at address, the orientation of the apparatus relative to the club head face and the club head deflection throughout the swing and may be combined with data from the accelerometer and gyroscope to create data that more accurately reflects a golf swing.
The data from a navigation system may be used to correct errors caused by drift in gyroscope measurements and signal noise from both accelerometer and gyroscope sensors. Examples of such navigation systems are MIT's Cricket system and the system described in “Low Cost Inertial Navigation: Learning to Integrate Noise and Find Your Way” by Kevin J. Walchko, Thesis Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science, University of Florida, 2002.
Cricket is an indoor location system for pervasive and sensor-based computing environments. Cricket provides fine-grained location information such as space identifiers, position coordinates, and orientation, to applications running on handheld devices, laptops, and sensor nodes for continuous object tracking Cricket is intended for use indoors or in urban areas where outdoor systems like the Global Positioning System (GPS) do not work well. It can provide distance ranging and positioning precision of between 1 and 3 cm, so applications that benefit from better accuracy than the cellular E-911 services and GPS will also find Cricket useful. Cricket is designed for low-power operation and can be used as a location-aware sensor computing node (running TinyOS), to which a variety of sensors can be attached. Cricket uses a combination of RF and ultrasound technologies to provide location information to attached host devices. Wall- and ceiling-mounted beacons placed through a building publish information on an RF channel. With each RF advertisement, the beacon transmits a concurrent ultrasonic pulse. Listeners attached to devices and mobiles listen for RF signals, and upon receipt of the first few bits, listen for the corresponding ultrasonic pulse. When this pulse arrives, the listener obtains a distance estimate for the corresponding beacon by taking advantage of the difference in propagation speeds between RF at the speed of light and ultrasound at the speed of sound. The listener runs algorithms that correlate RF and ultrasound samples (the latter are simple pulses with no data encoded on them) and that pick the best correlation. Even in the presence of several competing beacon transmissions, Cricket achieves good precision and accuracy quickly.
The inertial navigation system described by Walchko uses an inertial measurement unit (IMU) and a global positioning system (GPS) to allow inertial navigation in noisy environments, such as those outdoors. The IMU uses accelerometers and gyroscopes to interpolate positions between 1 HZ GPS positions. Walchko's system corrects bias from the IMU caused by the effects of gyroscope drift, temperature, hysteresis and vibrations.
Accordingly, it would be desirable to provide a lightweight attachment to a golfer's actual golf club that detects and measures the movement of a full golf swing, that analyzes the entire golf swing, that provides comprehensive statistics for every point of an entire swing, that displays the movement of the entire swing on a graphical display with the comprehensive statistics, that displays laser lines on a graphical display that would be drawn on the ground during the entire swing as if lasers were attached and linearly aligned to the head and the tail of the shaft of a golf club for swing plane analysis, and that coaches the golfer on how to improve the swing using theoretical and historical data. This can be accomplished by attaching an apparatus of negligible weight to the shaft or top of a golf club where the apparatus comprises a 3-axis accelerometer, a 3-axis gyroscope, computer memory, a microprocessor, a transmitter, and a battery such that it communicates with a computer application running on a mobile device, such as a smart phone, tablet computer, or a laptop computer. To compensate for differences in the angles that individual golfers address a ball, a 3-axis magnetometer can be used to select the target line on which a golfer wishes to aim. Additionally, it would also be desirable to include a camera in the lightweight attachment and to use image recognition software to measure the distance between the club head and the ball at address, the rotation of the club during the swing, and the movement of the club head relative to the movement of the shaft of the club. It would further be desirable to correct bias from the accelerometers and gyroscopes caused by the effects of gyroscope drift, temperature, hysteresis and vibrations in outdoor environments using a combination of RF and ultrasound technologies to provide location information to attached host devices. Accelerometer and gyroscope error would also be desirably corrected and made more precise by determining object speeds and coordinates using image sensors in three dimensions as part of the apparatus. Another desirable feature would be to utilize a camera on the tablet computer or other mobile device to capture and to automatically trim real-time video of the player's shot to create a video duplication of the animated view of the shot for side-by-side comparison so the user may see what actions of the user may be introducing errors or corrections in the swing.
The inventions discussed in connection with the described embodiment address these and other deficiencies of the prior art. The features and advantages of the present inventions will be explained in or apparent from the following description of the preferred embodiment considered together with the accompanying drawings.